Sand blasting apparatus



May 27, 1958 w. c. KOENIG SAND BLASTING APPARATUS 3 Sheets-Sheet 1 Filed Jan. 24, 1957 May 27, 1958 w. c. KOENIG SAND BLASTING APPARATUS 3 Sheets-Sheet 2 Filed Jan. 24, 1957 SMW LVN/mm 5 mm y 7, 1958 w. c. KOENIG SAND BLASTING APPARATUS 3 Sheets-Sheet 3 Filed Jan. 24, 1957 SM/443V Iii/[15122 5 Emmy StfltfiS. P aittentedMa; 27,1958

SAND BLASTING APPARATUS William C. Koenig, Milwaukee, Wis., assignor to Brant and Nielsen Company, Milwaukee, Wis., a corporation of Wisconsin Application January 24, 1957, Serial No. 636,153

1 Claim. (Cl. 51-8) This invention relates to sand blasting apparatus and has as its purpose to increase the capacity of such apparatus, by making. it possible to use much higher pressures and larger and heavier hoses.

The sand blasting of surfaces to be cleaned preparatory to painting, and also merely for the sake of cleaning as in the case of stone or brick walls, is now a common practice. Ordinarily this is done by an operator or workman stationed on a scaffold, or other suitable support, manually manipulating the discharge nozzle of the apparatus. Obviously, this has the serious disadvantage of entailing the presence of the operator directly in the working. zone, which makes this an extremely dirty and hazardous occupation, because of the inevitable abrasive dust which results from the blasting operation. It has a further disadvantage of limiting the volume of sand blasted against the surface, since a hose and nozzle which delivers much more than 120 cubic feet per minute at a pressure inthe neighborhood of 100 lbs. per square inch, cannot be safely handled for more than a short time by an operator stationed on a scaffold. The present invention overcomes these objections through the provision of an apparatus which may be controlled from a remote point and which not only supports the air line or. hose and the discharge nozzle at the end thereof, but also swings the same back and forth so that the stream of sand issuing from the nozzle sweeps across a substantial, uniformly wide area of the surface being sand blasted, as the apparatus moves across the surface.

By this invention, therefore, it is entirely possible and feasible to use a hose and nozzle capable of delivering as much as 600 cubic feet per minute at pressures even higher than 100 lbs. per square inch. 7

In sand blasting and painting of vertical surfaces, the scaffolds employed often are in the form of cages adapted to be suspended from above, and to be raised and lowered by power means. One such cage is illustrated in the Fisher Patent No. 2,112,837, issued. April 5, 1938. The present invention contemplates theruse of such power driven scaffolds or cages, and, to this end, it is another object of the invention to provide an apparatuswhich is readily attached to or mounted on a power driven scaffold or cage, and which 7 is entirely self-contained and includes means for swingably mounting the noule and adjacent portion of the hose and forautomatically swinging thenozzle back and fqrth across a surface to be sand blastedall Without interfering with power actuated elevation or descent of the scaffold or cage.

Another object of this invention is to provide a device of the character described which may be readily and easily attached to a cage-like scaffold or to any other suitable carriage or supporting structure by which the device may be moved across either vertical or horizontal surfaces to be sand blasted.

Still another object of this invention is to provide a device of the character described with mounting means so constructed that the entire device may be quickly and easily moved or swung to an out-of-the-way position,

2 without entailing detachment of any portion thereof from the supporting structure upon which it is mounted.

With the above and other objects in view, which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly defined by the appended claim, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claim.

The accompanying drawings illustrate two complete examples of the physical embodiments of the invention constructed according to the best modes so far devised for the practical application of the principles thereof, and in which:

Figure 1 is a perspective view of one embodiment of this invention, especially adapted for the sand blasting of vertical surfaces;

Figure 2 is a top plan view of the device of this invention per se, shown detached from the cage or carriage upon which it is mounted in Figure 1;

Figure 3 is a side view of the device and a portion of the carriage upon which it is mounted, and illustrating how the mounting of the device permits the same to be swung to an out-of-the-way position;

Figure 4 is a perspective view illustrating the device mounted on a carriage adapted for free movement across a floor, and illustrating how the apparatus is employed for sand blasting floors and the like; and

Figure 5 is a perspective view illustrating a modified way of imparting back and forth motion of the nozzle.

Referring now particularly to the accompanying drawings, the numeral 5 designates a sand blasting nozzle attached to the end of a supply hose 6. The hose 6 is connectible to a source of air under pressure, not shown, and also to a supply of sand which is to be entrained in the air stream and blasted from the nozzle against the surface to be cleaned or otherwise treated.

In keeping with the objectives of this invention, the hose 6 has a relatively large bore and, hence, it and the nozzle attached thereto are quite heavy. The pressure at which the air and entrained sand are discharged from the nozzle is about, or slightly higher than that heretofore employed in sand blasting, that is, in the range of to lbs. per square inch; but, because of the greatly increased size of the hose and nozzle, the volume of sand and air issuing from the nozzle may be as high as 600 cubic feet per minute, as compared to less than 120 cubic feet per minute with conventional equipment. This greatly increases the capacity of the unit, but also makes it impossible for a single operator or workmanto safely handle the nozzle. Even two men would have difliculty manipulating the nozzle under these conditions, Accordingly, the nozzle and the discharge end portion of the hose to which it is attached are mounted on a carriage indicated generally by the numeral 7. This carriage may be of the type which is suspended from overhead, as illustrated in Figure 1, in which event it would be more accurately described as a cage, and supported by cables 8, to be raised'and lowered overthe-surface toIbe sand blasted. Rollers 9 are preferably provided to hold the carriage ofi of this surface and guide its ascent and descent.

The means by which the nozzle and adjacent discharge end portion of the hose are connected to and supported fiom the carriage 7 comprises essentially a bracket 10 mounted on the carriage, an arm 11 to which the nozzle and discharge end portion of the hose are secured, as at 12, and a pivotal connection between the arm and the bracket. The mounting of the bracket 10 on the carriage may be effected in any desired manner and may comprise an upright supporting member 14 which is I of the apparatus.

removably clamped to carriage, and preferably has the right angles. to the pivotal connection 13. I The bracket 10 and all of the structure carried thereby thus-may be swung from its horizontal operative position illustrated in Figure 1, man out-of-the-way position in dicated in dotted lines in Figure 3, in which position these parts are swung clear of the carriage'top.

The specific conctructi on.ofthepivotal connection 13 between the bracket 10 and the arm 11 is, oi'course, susceptible to modification but, in the present instance, comprises a horizontally projecting bearing unit 17 fixed to theibracket 10 and in which a pivot post 18 on the adjacent end of-the arm llis rec'eived'so that the arm 11 and the nozzle and hose attached thereto maybe swung about the axis'of the post 18 which is vertical in the operative position of the device. 7 V

The specific manner in which the nozzle and hose are secured to the arm 13; is also susceptible to modification and, inthe present instance, is illustrated as comprising a pair of complementary upper and lower clamps 19-25) at each end of the arm, the lower clamps 2% being fixed to the arm.

The bracket'ltl not only pivotally supports the arm 11' and the hose and nozzle attached thereto, but also a tension on the bracket, and is so connected to this" extension as to permit the necessary swinging of the are other uses for the device of-this invention where an electric motor could be safely "employed in' lieu ofrthe has a gear reduction unit 31 mounted thereouto which I cylinder as the motor operates and swings the arm 11 back andforth.

The valveswith which fluid pressure motors are customarily equipped are housed in a valve honsing'indb cated generally by the numeral 26 which housing is reciprocates and thus swings or oscillates Le arm 1?. about the pivotal mounting 13, to thereby carry the noz zle back and forth across the surface to be sand-blastedl' The embodiment of the invention illustrated in'Fig ure 1 is especially'adapted for use in sand blastingihigh vertical walls, as for instance the sides of huge gasoline storage tanks, in which event the supporting cables 8 are 7 suitably anchored at the top of the tank and the control 7 -for the mechanism'by which the cablesare wound and unwound on their drums to raiseand lower the carriage,

.is on the ground where the operator may be safely and conveniently stationed. As will bereadily understood,

the work is done in slightly overlapping vertical swatches,

Hence, when fluid pressure supplied to the motor through a feed line 23, the ram 23 to adapt the device of this invention to the sand blasting of floors and other horizontal surfaces. For this pur:

pose, a carriage equipped with supporting wheels 3%), as

in Figure '4, is employed, and the support 14 is clamped to the top portion of the carriage. In all other respects,

though, the structure'illustrated irrFigure' l is the same as that of Figures 1, 2 and 3.

Since the sandblasting of the sides .of huge gasoline storage tanks is one of the uses for which this invention was particularly designed, 'it is preferable that the motorj employed to swing the nozzle back and forth be entirely free from the possibility of sparking, and for this'reason, an electric motor is not too'desirable. However, there fluid pressure operated motor, and, in this even, the arrangement illustrated in Figure '5 may be employedto advantage. In the drive here shown, the bracket 10 an electric drive motor 32 is secured,'and a drive shaft 33 projects from the gear reduction-unit; This drive shaft has a 'crank34 thereon which, in turn, iscomiected through alink 35 to the arm 11. e 1

From the foregoing description, taken in connection with the accompanying drawings, it will be readily ap parent to those skilled in this art that this invention pro vides a sand blasting apparatus of greatly increased cap'a' city, and one which, possesses the advantage of enabling the operator to control the same fromra distanceand" thereby avoid the dangerous and dirty working conditions which have always characterized past sand blasting.

operations. e

What is claimed 'as' my invention'is:

blast such surfaces as the sides of large oil tanks, comprising a hose. connected to a source of air under pressure and to a supply of sand to be entrained inthe air flowing through the hose; a nozzle on the end of the hose; a supporting member having means to secure the same to acarriage; a bracket; hinge means connecting the. bracket to.said supporting member; an arm; means pivotally' connecting the arm to the bracket for bodily.

movement therewith and for swinging movement of the arm relative to the bracket about an axis transverse to that of the hinge; means securing the nozzle and the V 7 adjacent portion of the-hose to the a'rm so that the nozzle partakes of all motion of the arm; a motor mounted on the bracket; and a driving connection between the .motor. and the through which the motor acts. to swing the arm-back and forth about the axis of its pivotal connection with the bracket without inter ferring with movement of the bracketv and .all .of the mounted without in anywise disturbing the operative re- I each of which is quite wide because of the high capacity Itis, of "course, also possible as shown Figure 4,

structure mounted thereon fabout the axis of thehinge connection between thebracket and the supporting strucrv ture, so that the entire apparatus may be swungtolan Refereuces Cited in'thefile ofthisi patent' 7 UNITED STATES PATENTS. 

